Why are there no built-in blogs in Facebook, VKontakte and others like them?

Question

Blogs

After all, it suggests itself.

Answer 1

I didn’t understand why VKontakte “notes” are not a blog. Primitive, of course, but a blog.

Answer 2

People don't need it. What percentage of social network users do you think will have a real blog?

Answer 3

Write notes.

Answer 4

the wall is a microblog ala twitter, the notes are a full-sized blog.